Intergroup retaliation and intra‐group praise gain: The effect of expected cooperation from the in‐group on intergroup vicarious retribution

Intergroup vicarious retribution is the phenomenon whereby, after an out‐group member attacks an in‐group member, a member of the victim's group retaliates against a member of the perpetrator's group. This study examined the effect of expected cooperation from the in‐group on intergroup vicarious retribution through intra‐group reputation based on praise gain and exclusion avoidance. In the experiment, we conducted a one‐on‐one match in which, after participants learned that an out‐group member (as the winner) had imposed a fine on an in‐group member (as the loser) in a previous round, winning participants were allowed to impose an arbitrary fine on the other losing out‐group member. As a result, participants imposed a larger fine on their out‐group member opponent in retaliation when they were expected by in‐group members to cooperate than when such cooperation was not expected. Furthermore, participants regarded a fine as intra‐group cooperation. Since a path analysis revealed a mediating effect of praise gain, but no mediating effect of exclusion avoidance, expected cooperation from in‐group members facilitated vicarious retribution because those involved in retribution sought praise from other in‐group members. These findings suggest that the intra‐group reputation dynamics of expected cooperation and praise gain escalate intergroup conflict.